A ruling Wednesday that upheld Louisiana's ban on gay marriage was the first time backers of same-sex marriage had lost in federal court since the Defense of Marriage Act was overturned. But the winning streak resumed Thursday, as a federal appeals court in Chicago affirmed decisions that overturned similar bans in Indiana and Wisconsin.

The ruling adds to the consensus favoring gay marriage in the federal courts, and made U.S. District Judge Martin Feldman look even more like an outlier. What did Feldman see differently?

A slippery slope

Feldman offered up some hypotheticals about what might happen if courts legalized same-sex marriage, statements some say equate gay marriage to incest:

"Inconvenient questions persist. For example, must the states permit or recognize a marriage between an aunt and niece? Aunt and nephew? Brother/brother? Father and child? May minors marry? Must marriage be limited to only two people? What about a transgender spouse? Is such a union same-gender or male-female? All such unions would undeniably be equally committed to love and caring for one another, just like the plaintiffs."

People who are against gay marriage don't hate gay people

Feldman writes that he was skeptical of the idea that Louisiana's ban on gay marriage "could only be inspired by hate and intolerance." Other courts have been willing to investigate claims of discrimination in gay marriage bans based on whether more benign fear, or confusion, toward gay people was the only reason.

"(Is) there even any rational basis for Louisiana's resistance to recognize same-sex marriages entered into in other states, or to authorize same-sex marriages in Louisiana? Plaintiffs contend not, and conclude that Louisiana's laws and Constitution can only be supported by a hateful animus. Defendants rejoin that the laws serve a central state interest of linking children to an intact family formed by their biological parents."

Feldman thinks states could have been motivated to preserve bans out of respect for the democratic process, or tradition.

"Of even more consequence, in this Court's judgment, defendants assert a legitimate state interest in safeguarding that fundamental social change, in this instance, is better cultivated through democratic consensus. This Court agrees.

"The Court is persuaded that a meaning of what is marriage that has endured in history for thousands of years, and prevails in a majority of states today, is not universally irrational on the constitutional grid."

Tradition!

Speaking of things that have endured for thousands of years, noted conservative jurist Richard Posner wrote in the 7th Circuit's opinion Thursday that tradition alone is no defense of marriage as solely for man-woman couples:

"Bad traditions that are historical realities such as cannibalism, foot-binding, and suttee, and traditions that from a public-policy standpoint are neither good nor bad -- such as trick-or-treating on Halloween. Tradition per se therefore cannot be a lawful ground for discrimination-regardless of the age of the tradition."

Feldman has a different take, noting that while some states have legalized gay marriage without court intervention, the concept of same-sex couples marrying was "nonexistent and even inconceivable until very recently."

"Many states have democratically chosen to recognize same-sex marriage. But until recent years, it had no place at all in this nation's history and tradition. Public attitude might be becoming more diverse, but any right to same-sex marriage is not yet so entrenched as to be fundamental."

That concept was one key to Feldman's ruling. If same-sex marriage is such a new concept, Feldman decided, it is not a "fundamental right" that can be protected by the constitution.

Marriage is about binding together families

Other courts have ruled that denying same-sex couples and their children the rights afforded to married spouses harms those families. Feldman believes "marriage's historically preeminent purpose of linking children to their biological parents," but doesn't consider other family dynamics.

"The fact that marriage has many differing, even perhaps unproved dimensions, does not render Louisiana's decision irrational. Nor does the opinion of a set of social scientists (ardently disputed by many others, it should be noted) that other associative forms may be equally stable, or the view that such judgments vilify a group (even though one finds them in a majority of the states, but not in all states).

In contrast, writing the 7th Circuit opinion, Posner points out that the institution of marriage binding opposite-sex couples has flaws.

"Heterosexuals get drunk and pregnant, producing unwanted children; their reward is to be allowed to marry. Homosexual couples do not produce unwanted children; their reward is to be denied the right to marry. Go figure."

The federal Defense of Marriage Act was a bad thing

The Supreme Court's decision in U.S. v. Windsor, which struck down portions of a federal law that denied recognition of marriages between same-sex couples, opened the doors for gay marriage cases.

Opponents of marriage bans say the high court's ruling endorses the rights of equal protection for gay couples. Feldman allows that the ruling just gives either side "something to hope for," but to his mind, Windsor knocked down the Defense of Marriage Act because the federal government was ignoring states' rights to regulate marriage on their own:

"Although both sides seek the safe haven of Windsor to their side of this national struggle, and it is certainly without dispute that the Supreme Court correctly discredited the tainted unconstitutional result that DOMA had on democratically debated and then adopted New York state law blessing same-sex marriages."